Method of electroplating.



4 1 UNI ED sTnTEs PATEN OFFICE.

LEO DAFI, on nu'rnnnronn, NEW JERSEY, ASSIGNORITO ELECTRO-CHEMICALRUBBER & MANUFACTURING COMPANY, A CORPORATION OF NEW J I'ERSEY.

METHOD OF ELEGTROPLATING.

Specification of Letters Patent.

Patented Oct". 29,1912;

No Drawing. DriginaI applieation'filed January 28, 1911, Serial No. 605,170. Divided and this application filed February 17, 1912. Serial No. 678,363.

To all whom it may concern: I

ofthe King of Great Britain, and a i'esident of Rutherford, in the county of Bergen, in the State of New Jersey, have 1n-' vented a new and Improved Method of Electroplating, of which the following is a; specification. v i

My invention relates to a method of electroplatin with a plurality of metals and is adapted plating bath contains a plurality of metals in solution or where the anodes are composed of a plurality of metals preferablyin the form ofan alloy.

My invention isparticularl'y useful when one of the metals'to be and such plating is carried on for the pur to the surface thus pose of attaching rubber formed by directvulcanization, as described in my pending application Serial No. 564,840 filed. June 3, 1910. 7

Although my invention may be practised with other metals and solutions and by the use of different steps, I shall describeit with reference to those disclosed in my pending applicationNo. 605,170, filed January 28,

1911, of whiohithis application isa division;

since it has great-utility in this connection. However, I do not wish to confine myself to the precise ingredients, proportions or steps \therein disclosed, since, obviously, these ingredients have well known chemical equivalents and since the: steps may be widely varied without departing from the spirit ofmy invention. I

' One methodof practising my invention and that described in my herein referredto pending application, No. 605,170, is as follows: I first cast an alloy ipontaining apcopper, 38 parts of molten metal thoroughly to obtain a homo nitric acid, using approximately one ounce of alloy, to .5

Baum. This solution is then diluted with' "water so that the resulting solution consapphire blue tains 2 oz. of alloy tralized withisneutralized for use in cases where the electro-' plated i's antimony geneous alloy, I then dissolve this alloy in:

ounces of. nitric acid at'36,

I then dilute this'unt il 1 gallon ofthe solution contain's'l oz. of the alloy. This completes one of the, solutions used'in the preparation of the electrolyte, which I shall call solution No. 1.

Another solution, which I shall call s0lution No.- 2,' is prepared in the following manner: I first. cast an alloy containing parts of copper and 40 parts of zinc; which I dissolve in nitric acid and dilute so that one ounce of the alloy is contained in onehalf a gallon. I then add ammonia to neutralize the solution in the same manner as in solution No. 1, and add about-12 ounces of potassium cyanid solution at a specific gravity of 1.200. I then dilute until 1 oz.

"of the alloy is contained in 1 gallon of the solution. I then, have two solutions No. 1,

proximately 1.032 to 1.035. and contains the antlmony, and No. 2, which will have a specific gravity 0151.030 to 1. 035 and is used as a diluent. During the -making of these solutions some loss will occur due to evaporation of water and nitric acid, so .that the quantities given above are not exact' I find it preferable to-keep the solutions at a temperature of approximately 200 Fahrenheit during the dissolution of the alloys. Solutions 1 and 2. are thenmixed together in variable proportions depending upon the antimony contained of the alloy it is desired to deposit, a greater proportion ofsolution N 0.1 being used if it is desired to obtain a deposit high in antimony and a greaterproportion of solntion'No.'2 being used if it is desired to secure-a deposit low in antimony, The electrolyte is then put in the plating tank and maintained at a 'temperature of 70 Fahrenheit, the article to be I solution to assume a clear light strawcolor. 5.5 Be it known that I, 'LEO DAFT, a subject which will have a specific gravity of applated forms thefiithode and the anodeconsists of an alloy of copper, zinc and antimony.- I find that a potential of about 3.76 volts is preferable for-this plating and that the distance between the cathode and anode should be approximately 10 centimeters I have discovered that I can vary the amountsof various metalsdeposited from an alloy anode by varying the proportions of the constituentmetals of the alloy, the bath remainingpractically constant in its proportions. Thus, ifI find that I wish to deposit an alloyhrf a; higher antimony con- 6 have described, Imay,

' current. decrease the relatlve amount of antimony 10 number of anodes of varying composition and make use of that best suited for the purpose; I have also, discovered that'the relative proportions of the metals constituting the alloy deposited may be varied by 15 varying the potential of the current used for electroplating. Thus using the same bath and alloy anode I may increase the amount of antimony by raismg the potential of the On the other hand, if I desire to accomplish this result by decreasing the potential of the current. I also find that a still greater increase in the potential of the current will increase the'rate deposited I cail 25 of deposition of zinc in an alloy such as described above'; I

Having described one method in which my invention may be practised, although obviously other equivalent methods may be used, what I claim and desire to secure by Letters Patent is:

' 1. The method'of electroplating from an I electrolyte formed of a plurality of metals in solution, one of whichis antimony, which consists in rent employed to vary the percentage ofanincrease the varying the potential of the cur-.

ea-ates timony deposited with respect to the other metals.

2. The method of electroplating from an electrolyte formed of a plurality of metals in solution, two of which are antimony and zinc, which consists in varying the potential of the current employed to vary the percentage of antimony and zinc deposited with respect to the other metals.

3. The method of electroplating from an anode of an alloy of plurality of metals, one of which is antimony, which consists in varying the potential of the current employed to vary the percentage of antimpny deposited with respect to the other metals.

4. The method of electroplating from an anode of an alloy of a plurality, of metals, two of which are antimony and zinc, which consists in varying the potential of the current employed to varythe percentage of antimony and zinc deposited with respect to the other metals. s I

5. The method of electroplating fromv an electrolyte formed of a plurality of metals in solution, -which consists in using an anode of an alloy of metals, one of which is antimony and varying the antimony content of the anode to vary the antimony content of the metal deposited.

In witness whereof I have hereunto set my hand in the presence or, two witnesses.

p LEO DAFT. W-itnesses': r.

WALTER S. JoNEs, MARGARET Mnoln'rrnn. 

